.clearfix {
    *zoom: 1;
}
.clearfix:after {
    content: ".";
    display: block;
    height: 0;
    line-height: 0;
    visibility: hidden;
    clear: both;
}
:root {
    --color-background: #242424;
    --white-color-background: #fff;
    color-scheme: light dark;
}
/* 监听操作系统主题模式 */
@media (prefers-color-scheme: dark) {
    body {
        background-color: var(--color-background);
    }
    :root {
        color: var(--white-color-background);
    }
}

@media (prefers-color-scheme: light) {
    :root {
        color: var(--color-background);
    }
    body {
        background-color: var(--white-color-background);
    }
    button {
        background-color: #f9f9f9;
    }
}
